1. Field of the Invention
The present invention relates to a high output light emitting diode (LED) and a method for fabricating the same wherein a sidewall of the LED is inclined and a reflective film is formed on the inclined sidewall to allow light emitted outside of the sidewall to reflect from the reflective film and to emit upward of the device, thereby enabling to improve a light output and dispensing with an additional passivation process.
2. Discussion of the Related Art
Generally, an LED is widely used in applied fields such as color bulletin boards, traffic lights, keypad light sources for mobile telephones, light sources for illumination and LCD backlights.
FIG. 1 is a cross-sectional view of a conventional LED. The LED includes a substrate (10) sequentially stacked thereon with an N-type semiconductor layer (11), an active layer (12) and a P-type semiconductor layer (13), mesa etched from the P-type semiconductor layer (13) to portions of the N-type semiconductor layer (11), a transparent electrode (14) formed on the P-type semiconductor layer (13), an N electrode (15) formed on the mesa-etched N-type semiconductor layer (11) and a P electrode (16) formed on the transparent electrode (14).
If current flows in the N electrode (15) and the P electrode (16) in the LED, light is generated from the active layer (12) and emitted outside of the device. Many attempts have been made to increase the light output of the LED, and a device manufacturing of flip chip structure is one of the attempts.
FIG. 2 is a mimetic cross-sectional view of a flip chip LED bonded to a sub mount substrate according to the prior art. Referring to the LED structure of FIG. 1, the flip chip LED is structured in such a manner that the P-type semiconductor layer (13) is stacked thereon with a reflective film (16) for P electrode, the reflective film (16) and the N electrode (15) are bonded to a sub mount substrate (30) by conductive bonding materials such as solders (20a. 20b), and light is emitted toward the substrate (10).
In other words, the flip chip type light device is such that the light emitted from the active layer (12) is reflected from the reflective film (16) to be emitted outside of the device via the substrate (10).
However, the light emitted from the flip chip type light device is reflected from an entire surface of the device to the disadvantage of wasting the light emitted from the sidewall of the device.
Particularly, in the case of a cleavage plane of the device, part of light emitted from a sidewall of the device is reflected from the cleavage plane, confined inside the device and cannot be emitted therefrom, thereby resulting in decreased light emission from the device.